Analytical solutions for the restraint effect of isolation piles against tunneling-induced vertical ground displacements

查看全文 作　　者：Liqiang [1,2,3]Cao;Xiangsheng [2,3]Chen;Xing-Tao [2,3]Lin;Dong [2,3]Su;Huangcheng [4]Fang;Dechun [1]Lu 机构地区：[1]Institute of Geotechnical and Underground Engineering,Beijing University of Technology,Beijing,100124,China;[2]Underground Polis Academy,Shenzhen University,Shenzhen,518060,China;[3]College of Civil and Transportation Engineering,Shenzhen University,Shenzhen,518060,China;[4]Department of Civil and Environmental Engineering,The Hong Kong Polytechnic University,Hung Hom,Kowloon,Hong Kong,China 出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》索引2023年第15卷第10期,共15页 基　　金：support by the National Natural Science Foundation of China(Grant Nos.52108376 and 51908371);China Postdoctoral Science Foundation(Grant No.2022T150436). 摘　　要：This paper presents a simplified elastic continuum method for calculating the restraint effect of isolation piles on tunneling-induced vertical ground displacement,which can consider not only the relative sliding of the pile‒soil interface but also the pile rowesoil interaction.The proposed method is verified by comparisons with existing theoretical methods,including the boundary element method and the elastic foundation method.The results reveal the restraining mechanism of the isolation piles on vertical ground displacements due to tunneling,i.e.the positive and negative restraint effects exerted by the isolation piles jointly drive the ground vertical displacement along the depth direction from the original tunneling-induced nonlinear variation situation to a relatively uniform situation.The results also indicate that the stiffness of the pile‒soil interface,including the pile shaft‒surrounding soil interface and pile tip-supporting soil interface,describes the strength of the pile‒soil interaction.The pile rows can confine the vertical ground displacement caused by the tunnel excavation to the inner side of the isolation piles and effectively prevent the vertical ground displacement from expanding further toward the outer side of the isolation piles. 关 键 词：Restraining mechanism Restraint effect Isolation piles Ground displacement TUNNELING